Hi,

When configuring spi_bus_config_t, by default max_transfer_sz, is 4094 Bytes.
i.g.
spi_bus_config_t buscfg={
.miso_io_num=PIN_NUM_MISO,
.mosi_io_num=PIN_NUM_MOSI,
.sclk_io_num=PIN_NUM_CLK,
.quadwp_io_num=-1,
.quadhd_io_num=-1,
.max_transfer_sz=0 //in bytes, default is 4094
};

If you ...

Hi @squonk11,

First time I hear this "peculiarity", do you have a source where to find more about it?
I have seen some posts regarding 4 bytes lost, when using SPI slave mode. I am not currently using the slave mode to verify but that is different from your use case.

You can use polling as
trans ...

Hi,

I have struggled with this matter before.
There are a few options to address, and it depends very much on:

What is your data size (Tx) in bytes? (i.g. 3 bytes 0x06 0x00 0x00)
Are they repetitive (same data sent over and over)? (i.g. last 3 bytes to transmit for lets say 3600 times)
Are you ...